My experience with amtrak was surprisingly pleasant. My morning train in to chicago was sterile-ly clean and almost empty, but took 4 hours (scheduled for 2.75). My evening train smelled like extreme BO, but only took 2 hours (scheduled again for 2.75). This state of affairs can be described as "surprisingly pleasant" as I expected BOTH legs of the trip to take 4 hours AND smell like extreme BO.
Despite my friends' urgent warnings, no indigent peoples tried to talk to me or make friends on either train. I think I will use the amtrak again! Way less stressful than driving in the city, and not any more expensive with gas in chicago being up to $4 a gallon.